Inventory is a way to limit the number of users that can select a particular choice for an item. Once all of the choice's allotted units are taken, it can no longer be selected.
Define an inventory amount for a compatible item by going to "Form Editor", editing the item, and clicking the Inventory tab. The values entered here set the total inventory allowed for the item's choices. A value of zero ("0") will not allow any results, effectively disabling the choice. Leave a setting empty for no inventory.
Inventory information, including the total taken and allowed, can be viewed in different results formats. For a complete listing of the inventory for your form, go to "Results->Analytics" and click the Inventory Report tab.
With the exception of the Quantity List item, all inventory-capable items can be used in conjunction with the Text Quantity item. Adding a Text Quantity item immediately before an inventory item will multiply the user's choices by the amount entered in the Text Quantity item. This allows the single result to take more than one unit for each choice. Moving or deleting the Text Quantity item will cause the allocated inventory for the saved results to be adjusted accordingly.
The default "Insufficient Quantity Remaining" error message can be changed on the "Form Settings->Custom Text" page. This will be shown to the user if their selections exceed the remaining inventory for an item.